mesa: Kill gl_fragment_program::FogOption with fire

All drivers expect this to always be GL_NONE.  Don't let there be any
opportunity for a bad value to leak out and infect some unsuspecting
driver.  If any driver for hardware that had fixed-function
per-fragment fog (i915 and perhaps some r300-ish) was ever going to
add support, it would have done it by now.

Reviewed-by: Eric Anholt <[email protected]>
Acked-by: Corbin Simpson <[email protected]>
Acked-by: Alex Deucher <[email protected]>

1 files changed, 6 insertions, 12 deletions

diff --git a/src/mesa/program/arbprogparse.c b/src/mesa/program/arbprogparse.c
index 7f778c3c381..dffc8abf735 100644
--- a/src/mesa/program/arbprogparse.c
+++ b/src/mesa/program/arbprogparse.c
@@ -116,20 +116,11 @@ _mesa_parse_arb_fragment_program(struct gl_context* ctx, GLenum target,
          program->Base.SamplersUsed |= (1 << i);
    }
    program->Base.ShadowSamplers = prog.ShadowSamplers;
-   switch (state.option.Fog) {
-   case OPTION_FOG_EXP:    program->FogOption = GL_EXP;    break;
-   case OPTION_FOG_EXP2:   program->FogOption = GL_EXP2;   break;
-   case OPTION_FOG_LINEAR: program->FogOption = GL_LINEAR; break;
-   default:                program->FogOption = GL_NONE;   break;
-   }
    program->OriginUpperLeft = state.option.OriginUpperLeft;
    program->PixelCenterInteger = state.option.PixelCenterInteger;
 
    program->UsesKill            = state.fragment.UsesKill;
 
-   if (program->FogOption)
-      program->Base.InputsRead |= FRAG_BIT_FOGC;
-
    if (program->Base.Instructions)
       free(program->Base.Instructions);
    program->Base.Instructions = prog.Instructions;
@@ -143,12 +134,15 @@ _mesa_parse_arb_fragment_program(struct gl_context* ctx, GLenum target,
     * there's no hardware that wants to do fog in a discrete stage separate
     * from the fragment shader.
     */
-   if (program->FogOption != GL_NONE) {
+   if (state.option.Fog != OPTION_NONE) {
+      static const GLenum fog_modes[4] = {
+	 GL_NONE, GL_EXP, GL_EXP2, GL_LINEAR
+      };
+
       /* XXX: we should somehow recompile this to remove clamping if disabled
        * On the ATI driver, this is unclampled if fragment clamping is disabled
        */
-      _mesa_append_fog_code(ctx, program, GL_TRUE);
-      program->FogOption = GL_NONE;
+      _mesa_append_fog_code(ctx, program, fog_modes[state.option.Fog], GL_TRUE);
    }
 
 #if DEBUG_FP